Abstract: Circuits and methods for suppressing integrated circuit leakage currents are described. Many of these circuits and methods are particularly well-suited for use in dynamic memory circuits. Examples describe the use of power, ground, or both and power and ground source transistors used for generating virtual voltages. An aspect of the invention describes lowering refresh current. An aspect describes reducing the standby current. An aspect of the invention describes lowering leakage resulting from duplicated circuits, such as row decoders and word line drivers. An aspect describes methods of performing early wake-up of source transistors. A number of source transistor control mechanisms are taught. Circuit layouts methods are taught for optimizing integrated circuit layouts using the source transistors.

Abstract: An apparatus and method for reducing power consumption within dynamic memory devices having internal self-refresh circuitry. The circuits for generating isolator control (ISO), pre-decoded row address (PXID) and/or word enable (WE) signals are configured in response to receipt of self-refresh and refresh counter signals to output different timing and sequencing when in self-refresh mode than when in normal mode of the memory device. Conventionally, ISO signals are controlled from a block selection circuit which also controls bit line equalization (BLEQ) and sense amplifier enable (SAPN). While in conventional circuits the PXID and WE signals are generated in response to the output of the address decoder and thus have a fixed timing in relation to the output of the address decoder. The use of different timing and sequencing can lower power consumption, such as by outputting fewer signal transitions per block during self-refresh.

Abstract: Circuits and methods for suppressing integrated circuit leakage currents are described. Many of these circuits and methods are particularly well-suited for use in dynamic memory circuits. Examples describe the use of power, ground, or both and power and ground source transistors used for generating virtual voltages. An aspect of the invention describes lowering refresh current. An aspect describes reducing the standby current. An aspect of the invention describes lowering leakage resulting from duplicated circuits, such as row decoders and word line drivers. An aspect describes methods of performing early wake-up of source transistors. A number of source transistor control mechanisms are taught. Circuit layouts methods are taught for optimizing integrated circuit layouts using the source transistors.

Abstract: Circuits and methods are described for reducing leakage current and speeding access within dynamic random access memory circuit devices. A number of beneficial aspects are described. A circuit is described for an enhanced sense amplifier utilizing complementary drain transistors coupled to the sense or restore signals and driven by gate voltages which extend outside of the voltage range between VSS and VDD. The drain transistors are self reverse-biased in a standby mode. A method is also described for reducing leaking in non-complementary sense amplifiers by modifying the sense and restore gate voltages. Another aspect is a new negative word line method utilizing stacked pull-down transistors and a multi-step control circuit. In addition a level shifter scheme is described for preventing unwanted current flow between voltage sources while discharging control signal PX.

Abstract: Source transistor configurations are described for reducing leakage and delay within integrated circuits. Virtual power and ground nodes are supported with the use of stacked transistor configurations, such as a two transistor stack between a first virtual supply connection and VSS, and a second virtual supply connection and VDD. Gate drives of these stacked transistors are modulated with different voltage levels in response to the operating power mode of the circuit, for example active mode, active-standby mode, and deep power-down mode. Means for driving these source stacks are described. In one embodiment separate virtual nodes are adapted for different types of circuits, such as buffers, row address strobe, and column address strobe. Other techniques, such as directional placement of the transistors is also described.

Abstract: An apparatus and method for reducing power consumption within dynamic memory devices having internal self-refresh circuitry. The circuits for generating isolator control (ISO), pre-decoded row address (PXID) and/or word enable (WE) signals are configured in response to receipt of self-refresh and refresh counter signals to output different timing and sequencing when in self-refresh mode than when in normal mode of the memory device. Conventionally, ISO signals are controlled from a block selection circuit which also controls bit line equalization (BLEQ) and sense amplifier enable (SAPN). While in conventional circuits the PXID and WE signals are generated in response to the output of the address decoder and thus have a fixed timing in relation to the output of the address decoder. The use of different timing and sequencing can lower power consumption, such as by outputting fewer signal transitions per block during self-refresh.

Abstract: An SRAM circuit structure and method for reducing leakage currents and/or increasing the speed of the devices. Various forms of SRAM devices may be fabricated utilizing the techniques, such as single port and dual port RAM devices. By way of example the SRAM structure utilizes separate write and read lines, splits the circuit into portions which can benefit from having differing threshold levels, and can allow splitting read path transistors for connection to a first terminal and a virtual node connected to a source transistor. The structure is particularly well suited for forming transistors in a combination of NMOS and PMOS, or solely in NMOS. Memory arrays may be organized according to the invention in a number of different distributed or lumped arrangements with the reference read paths and sense blocks being either shared or dedicated.

Abstract: Dynamic Random Access Memory (DRAM) circuits and methods are described for reducing leakage and increasing repaired yield. These objects are accomplished according to the invention by grouping refresh cycles within a single activation of power control, the use of limiting circuits or fuses to mitigate power losses associated with micro-bridging of bit-lines and word-lines, modulating the bit-line voltage at the end of precharge cycles, configuring refresh control circuits to use redundant word-lines in generating additional refresh cycles for redundant rows of memory cells, and combinations thereof. In one aspect, word-line fuses indicate modes of use as: unused, replacement, additional refresh, and replacement with additional refresh. The refresh control circuit utilizes these modes in combination with the X-address stored in the word-line fuses for controlling the generation of additional refresh cycles toward overcoming insufficient data retention intervals in select memory cell rows.

Abstract: Dynamic Random Access Memory (DRAM) circuits and methods are described for reducing leakage and increasing repaired yield. These objects are accomplished according to the invention by grouping refresh cycles within a single activation of power control, the use of limiting circuits or fuses to mitigate power losses associated with micro-bridging of bit-lines and word-lines, modulating the bit-line voltage at the end of precharge cycles, configuring refresh control circuits to use redundant word-lines in generating additional refresh cycles for redundant rows of memory cells, and combinations thereof. In one aspect, word-line fuses indicate modes of use as: unused, replacement, additional refresh, and replacement with additional refresh. The refresh control circuit utilizes these modes in combination with the X-address stored in the word-line fuses for controlling the generation of additional refresh cycles toward overcoming insufficient data retention intervals in select memory cell rows.

Abstract: Circuits and methods are described for reducing leakage current and speeding access within dynamic random access memory circuit devices. A number of beneficial aspects are described. A circuit is described for an enhanced sense amplifier utilizing complementary drain transistors coupled to the sense or restore signals and driven by gate voltages which extend outside of the voltage range between VSS and VDD. The drain transistors are self reverse-biased in a standby mode. A method is also described for reducing leaking in non-complementary sense amplifiers by modifying the sense and restore gate voltages. Another aspect is a new negative word line method utilizing stacked pull-down transistors and a multi-step control circuit. In addition a level shifter scheme is described for preventing unwanted current flow between voltage sources while discharging control signal PX.

Abstract: Circuits and methods are described for reducing leakage current and speeding access within dynamic random access memory circuit devices. A number of beneficial aspects are described. A circuit is described for an enhanced sense amplifier utilizing complementary drain transistors coupled to the sense or restore signals and driven by gate voltages which extend outside of the voltage range between VSS and VDD. The drain transistors are self reverse-biased in a standby mode. A method is also described for reducing leaking in non-complementary sense amplifiers by modifying the sense and restore gate voltages. Another aspect is a new negative word line method utilizing stacked pull-down transistors and a multi-step control circuit. In addition a level shifter scheme is described for preventing unwanted current flow between voltage sources while discharging control signal PX.

Abstract: A CMOS constant voltage generator circuit having input and output stages and at least one compensation stage. Each stage can comprise a single transistor or more typically a transistor stack. Current mirroring is performed between the input stage and compensation stage, as well as preferably between the input stage and output stage. The compensation stage also provides additional biasing to a transistor in the output stage to increase voltage regulation. Optionally, degeneration resistors (passive or active) are coupled to the source side, drain side, or a combination of source and drain sides in the compensation and output stages. Optionally, additional diode-coupled transistors are incorporated in the transistor stack of the output stage. The circuit provides accurate voltage reference (Vref) output with lowered sensitivity to temperature and supply voltage.

Abstract: Circuits and methods for suppressing integrated circuit leakage currents are described. Many of these circuits and methods are particularly well-suited for use in dynamic memory circuits. Examples describe the use of power, ground, or both and power and ground source transistors used for generating virtual voltages. An aspect of the invention describes lowering refresh current. An aspect describes reducing the standby current. An aspect of the invention describes lowering leakage resulting from duplicated circuits, such as row decoders and word line drivers. An aspect describes methods of performing early wake-up of source transistors. A number of source transistor control mechanisms are taught. Circuit layouts methods are taught for optimizing integrated circuit layouts using the source transistors.

Abstract: An SRAM circuit structure and method for reducing leakage currents and/or increasing the speed of the devices. Various forms of SRAM devices may be fabricated utilizing the techniques, such as single port and dual port RAM devices. By way of example the SRAM structure utilizes separate write and read lines, splits the circuit into portions which can benefit from having differing threshold levels, and can allow splitting read path transistors for connection to a first terminal and a virtual node connected to a source transistor. The structure is particularly well suited for forming transistors in a combination of NMOS and PMOS, or solely in NMOS. Memory arrays may be organized according to the invention in a number of different distributed or lumped arrangements with the reference read paths and sense blocks being either shared or dedicated.

Abstract: Circuits and methods are described for reducing leakage current and speeding access within dynamic random access memory circuit devices. A number of beneficial aspects are described. A circuit is described for an enhanced sense amplifier utilizing complementary drain transistors coupled to the sense or restore signals and driven by gate voltages which extend outside of the voltage range between VSS and VDD. The drain transistors are self reverse-biased in a standby mode. A method is also described for reducing leaking in non-complementary sense amplifiers by modifying the sense and restore gate voltages. Another aspect is a new negative word line method utilizing stacked pull-down transistors and a multi-step control circuit. In addition a level shifter scheme is described for preventing unwanted current flow between voltage sources while discharging control signal PX.

Abstract: Memory circuits and methods are described providing an interface with high density dynamic memory (DRAM), such 1T1C (1 transistor and 1 capacitor) memory cells, providing full compatibility with static memory (SRAM). The circuitry overcomes the shortcomings with DRAM, such as associated with the restore and refresh operations, which have prevented full utilization of DRAM cores with SRAM compatible devices. The circuit can incorporate a number of inventive aspects, either singly or more preferably in combination, including a pulsed word line structure for limiting the maximum page mode cycle time, an address duration compare function with optional address buffering, and a late write function wherein the write operation commences after the write control signals are disabled.